Thursday, August 15, 2013

New paper finds ocean 'acidification' doesn't affect young corals

A new paper published in the Marine Ecology Progress Series finds young corals do not suffer any apparent effects from ocean 'acidification', stating "None of the early life-history stages we studied were consistently affected by reduced pH. Our results suggest that there will be no direct ecological effects of ocean acidification on the early life-history stages of reef corals, at least in the near future." Other peer-reviewed publications have demonstrated that prior claims about ecological effects from ocean acidification have been overblown, increased CO2 dissolution in the oceans increases calcificationof shellfish and coral, and that corals evolved at a time when CO2 levels were 15 times higher than the present.

ABSTRACT: Until recently, research into the consequences of oceanic uptake of CO2 for corals focused on its effect on physiological processes, in particular, calcification. However, events early in the life history of corals are also likely to be vulnerable to changes in ocean chemistry caused by increases in the atmospheric concentration of CO2 (ocean acidification). We tested the effect of reduced pH on embryonic development, larval survivorship and metamorphosis of 3 common scleractinian corals from the Great Barrier Reef. We used 4 treatment levels of pH, corresponding to the current level of ocean pH and 3 values projected to occur later this century. None of the early life-history stages we studied were consistently affected by reduced pH. Our results suggest that there will be no direct ecological effects of ocean acidification on the early life-history stages of reef corals, at least in the near future.